Electronic circuits/devices may be formed by mounting electrical components on a substrate, such as a printed circuit board (PCB) or printed wire board (PWB), and interconnecting the electrical components. In addition, it may be desirable to electrically connect two substrates, such as two PCBs and/or two PWBs to permit electrical components on the substrates to operate in a coordinated manner. Interconnection of electrical components on a substrate, and interconnection of substrates, may typically be accomplished using soldered or bonded wires, metal traces, or the like.
Conductive silicone and conductive epoxies have been used as conductive adhesives. For example, conductive silicone has been used to form conductive gaskets for mounting electrical parts, to form electrically conductive sealants, and to provide electrical shielding.
Conductive epoxy has also been used to mount components onto headers. For example, conductive epoxy has been used to mount a light emitting diode (LED) to a metal cup in a package, such as a conventional T-1¾ LED package. Typically, an LED chip includes a substrate, an n-type epitaxial region formed on the substrate and a p-type epitaxial region formed on the n-type epitaxial region (or vice-versa). In order to use an LED chip in a circuit, it is known to enclose an LED chip in a package to provide environmental and/or mechanical protection, color selection, focusing and the like. In a typical LED package, an LED chip is mounted on a reflective cup by means of a solder bond or conductive epoxy. One or more wirebonds connect an ohmic contact of the LED chip to a lead. The entire assembly is then encapsulated in a protective resin, which may be molded in the shape of a lens to collimate the light emitted from the LED chip. Such a package, which may provide a useful point source of light, has been used in numerous applications, such as indicator lights, display elements, and the like.
However, for more complex applications, such as solid state backlighting, it may be desirable to mount an LED chip onto a substrate, such as a PCB/PWB, and to interconnect the LED chip with one or more other electrical elements on the PCB/PWB. Such electrical interconnections may require complex processing that may be difficult to configure and/or may require inflexible designs that may be relatively difficult to modify.